This avoids an unbounded allocation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
For the L1 table to loaded for an internal snapshot, the code allocated
only enough memory to hold the currently active L1 table. If the
snapshot's L1 table is actually larger than the current one, this leads
to a buffer overflow.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The qcow2 code assumes that s->snapshots is non-NULL if s->nb_snapshots
!= 0. By having the initialisation of both fields separated in
qcow2_open(), any error occuring in between would cause the error path
to dereference NULL in qcow2_free_snapshots() if the image had any
snapshots.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
bs->total_sectors is not the highest possible sector number that could
be involved in a copy on write operation: VM state is after the end of
the virtual disk. This resulted in wrong values for the number of
sectors to be copied (n).
The code that checks for the end of the image isn't required any more
because the code hasn't been calling the block layer's bdrv_read() for a
long time; instead, it directly calls qcow2_readv(), which doesn't error
out on VM state sector numbers.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Both compressed and uncompressed I/O is buffered. dmg_open() calculates
the maximum buffer size needed from the metadata in the image file.
There is currently a buffer overflow since ->lengths[] is accounted
against the maximum compressed buffer size but actually uses the
uncompressed buffer:
switch (s->types[chunk]) {
case 1: /* copy */
ret = bdrv_pread(bs->file, s->offsets[chunk],
s->uncompressed_chunk, s->lengths[chunk]);
We must account against the maximum uncompressed buffer size for type=1
chunks.
This patch fixes the maximum buffer size calculation to take into
account the chunk type. It is critical that we update the correct
maximum since there are two buffers ->compressed_chunk and
->uncompressed_chunk.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The DMG metadata is stored as uint64_t, so use the same type for
sector_num. int was a particularly poor choice since it is only 32-bit
and would truncate large values.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Chunk length and sectorcount are used for decompression buffers as well
as the bdrv_pread() count argument. Ensure that they have reasonable
values so neither memory allocation nor conversion from uint64_t to int
will cause problems.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Use the right types instead of signed int:
size_t new_size;
This is a byte count for g_realloc() that is calculated from uint32_t
and size_t values.
uint32_t chunk_count;
Use the same type as s->n_chunks, which is used together with
chunk_count.
This patch is a cleanup and does not fix bugs.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It is not necessary to check errno for EINTR and the block layer does
not produce short reads. Therefore we can drop the loop that attempts
to read a compressed chunk.
The loop is buggy because it incorrectly adds the transferred bytes
twice:
do {
ret = bdrv_pread(...);
i += ret;
} while (ret >= 0 && ret + i < s->lengths[chunk]);
Luckily we can drop the loop completely and perform a single
bdrv_pread().
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When a terminator is reached the base for offsets and sectors is stored.
The following records that are processed will use this base value.
If the first record we encounter is a terminator, then calculating the
base values would result in out-of-bounds array accesses. Don't do
that.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Clean up the mix of tabs and spaces, as well as the coding style
violations in block/dmg.c. There are no semantic changes since this
patch simply reformats the code.
This patch is necessary before we can make meaningful changes to this
file, due to the inconsistent formatting and confusing indentation.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The size in bytes is assigned to an int later, so check that instead of
the number of entries.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In order to avoid integer overflows.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If the size becomes larger than what qcow2_open() would accept, fail the
growing operation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This ensures that the checks catch all invalid cluster indexes
instead of returning the refcount of a wrong cluster.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
free_cluster_index is only correct if update_refcount() was called from
an allocation function, and even there it's brittle because it's used to
protect unfinished allocations which still have a refcount of 0 - if it
moves in the wrong place, the unfinished allocation can be corrupted.
So not using it any more seems to be a good idea. Instead, use the
first requested cluster to do the calculations. Return -EAGAIN if
unfinished allocations could become invalid and let the caller restart
its search for some free clusters.
The context of creating a snapsnot is one situation where
update_refcount() is called outside of a cluster allocation. For this
case, the change fixes a buffer overflow if a cluster is referenced in
an L2 table that cannot be represented by an existing refcount block.
(new_table[refcount_table_index] was out of bounds)
[Bump the qemu-iotests 026 refblock_alloc.write leak count from 10 to
11.
--Stefan]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
len could become negative and would pass the check then. Nothing bad
happened because bdrv_pread() happens to return an error for negative
length values, but make variables for sizes unsigned anyway.
This patch also changes the behaviour to error out on invalid lengths
instead of silently truncating it to 1023.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This avoids an unbounded allocation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This avoid unbounded memory allocation and fixes a potential buffer
overflow on 32 bit hosts.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The end of the refcount table must not exceed INT64_MAX so that integer
overflows are avoided.
Also check for misaligned refcount table. Such images are invalid and
probably the result of data corruption. Error out to avoid further
corruption.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Limit the in-memory reference count table size to 8 MB, it's enough in
practice. This fixes an unbounded allocation as well as a buffer
overflow in qcow2_refcount_init().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Header, header extension and the backing file name must all be stored in
the first cluster. Setting the backing file to a much higher value
allowed header extensions to become much bigger than we want them to be
(unbounded allocation).
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This fixes an unbounded allocation for s->unknown_header_fields.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
curl_read_cb is callback function for libcurl when data arrives. The
data size passed in here is not guaranteed to be within the range of
request we submitted, so we may overflow the guest IO buffer. Check the
real size we have before memcpy to buffer to avoid overflow.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Other variables (e.g. sectors_per_block) are calculated using these
variables, and if not range-checked illegal values could be obtained
causing infinite loops and other potential issues when calculating
BAT entries.
The 1.00 VHDX spec requires BlockSize to be min 1MB, max 256MB.
LogicalSectorSize is required to be either 512 or 4096 bytes.
Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The maximum blocks_in_image is 0xffffffff / 4, which also limits the
maximum disk_size for a VDI image to 1024TB. Note that this is the maximum
size that QEMU will currently support with this driver, not necessarily the
maximum size allowed by the image format.
This also fixes an incorrect error message, a bug introduced by commit
5b7aa9b56d (Reported by Stefan Weil)
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This fixes some cases of division by zero crashes.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This adds checks to make sure that max_table_entries and block_size
are in sane ranges. Memory is allocated based on max_table_entries,
and block_size is used to calculate indices into that allocated
memory, so if these values are incorrect that can lead to potential
unbounded memory allocation, or invalid memory accesses.
Also, the allocation of the pagetable is changed from g_malloc0()
to qemu_blockalign().
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
32 bit truncation could let us access the wrong offset in the image.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This fixes two possible division by zero crashes: In bochs_open() and in
seek_to_sector().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It should neither become negative nor allow unbounded memory
allocations. This fixes aborts in g_malloc() and an s->catalog_bitmap
buffer overflow on big endian hosts.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Gets us rid of integer overflows resulting in negative sizes which
aren't correctly checked.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is an on-disk structure, so offsets must be accurate.
Before this patch, sizeof(bochs) != sizeof(header_v1), which makes the
memcpy() between both invalid. We're lucky enough that the destination
buffer happened to be the larger one, and the memcpy size to be taken
from the smaller one, so we didn't get a buffer overflow in practice.
This patch unifies the both structures, eliminating the need to do a
memcpy in the first place. The common fields are extracted to the top
level of the struct and the actually differing part gets a union of the
two versions.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
cloop stores the number of compressed blocks in the n_blocks header
field. The file actually contains n_blocks + 1 offsets, where the extra
offset is the end-of-file offset.
The following line in cloop_read_block() results in an out-of-bounds
offsets[] access:
uint32_t bytes = s->offsets[block_num + 1] - s->offsets[block_num];
This patch allocates and loads the extra offset so that
cloop_read_block() works correctly when the last block is accessed.
Notice that we must free s->offsets[] unconditionally now since there is
always an end-of-file offset.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The offsets[] array allows efficient seeking and tells us the maximum
compressed data size. If the offsets are bogus the maximum compressed
data size will be unrealistic.
This could cause g_malloc() to abort and bogus offsets mean the image is
broken anyway. Therefore we should refuse such images.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Limit offsets_size to 512 MB so that:
1. g_malloc() does not abort due to an unreasonable size argument.
2. offsets_size does not overflow the bdrv_pread() int size argument.
This limit imposes a maximum image size of 16 TB at 256 KB block size.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The following integer overflow in offsets_size can lead to out-of-bounds
memory stores when n_blocks has a huge value:
uint32_t n_blocks, offsets_size;
[...]
ret = bdrv_pread(bs->file, 128 + 4, &s->n_blocks, 4);
[...]
s->n_blocks = be32_to_cpu(s->n_blocks);
/* read offsets */
offsets_size = s->n_blocks * sizeof(uint64_t);
s->offsets = g_malloc(offsets_size);
[...]
for(i=0;i<s->n_blocks;i++) {
s->offsets[i] = be64_to_cpu(s->offsets[i]);
offsets_size can be smaller than n_blocks due to integer overflow.
Therefore s->offsets[] is too small when the for loop byteswaps offsets.
This patch refuses to open files if offsets_size would overflow.
Note that changing the type of offsets_size is not a fix since 32-bit
hosts still only have 32-bit size_t.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Avoid unbounded s->uncompressed_block memory allocation by checking that
the block_size header field has a reasonable value. Also enforce the
assumption that the value is a non-zero multiple of 512.
These constraints conform to cloop 2.639's code so we accept existing
image files.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The mirror blockjob coroutine rate-limits itself by sleeping. The
coroutine also performs I/O asynchronously so it's important that the
aio callback doesn't wake the coroutine early as that breaks
rate-limiting.
Reported-by: Joaquim Barrera <jbarrera@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The throttling delay calculation was using an inaccurate sector count to
calculate the time to sleep. This broke rate-limiting for the block
mirror job.
Move the delay calculation into mirror_iteration() where we know how
many sectors were transferred. This lets us calculate an accurate delay
time.
Reported-by: Joaquim Barrera <jbarrera@ac.upc.edu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
if an NFS operation fails we should report what libnfs knows
about the failure. It is likely more than just an error code.
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If qcow2_alloc_clusters() fails, new_offset and ret will both be
negative after the fail label, thus passing the first if condition and
subsequently resulting in a call of qcow2_free_clusters() with an
invalid (negative) offset parameter. Fix this by introducing a new label
"fail_free_cluster" which is only invoked if new_offset is indeed
pointing to a newly allocated cluster that should be cleaned up by
freeing it.
While we're at it, clean up the whole fail path. qcow2_cache_put()
should (and actually can) never fail, hence the return value can safely
be ignored (aside from asserting that it indeed did not fail).
Furthermore, there is no reason to give QCOW2_DISCARD_ALWAYS to
qcow2_free_clusters(), a mere QCOW2_DISCARD_OTHER will suffice.
Ultimately, rename the "fail" label to "done", as it is invoked both on
failure and success.
Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Contrary to the comment describing this function's behavior, it does not
return 0 on success, but rather the offset of the newly allocated
cluster. This patch adjusts the comment accordingly to reflect the
actual behavior.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
nbd_receive_reply() is called by the event loop whenever data is
available or the socket has been closed by the remote side.
This patch closes the socket when an error occurs to prevent the
nbd_receive_reply() handler from being called indefinitely after the
connection has failed.
Note that we were already correctly returning EIO for pending requests
but leaving the nbd_receive_reply() handler registered resulted in high
CPU consumption and a flood of error messages.
Reuse nbd_teardown_connection() to close the socket.
Reported-by: Zhifeng Cai <bluewindow@h3c.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
On 32-bit hosts, some compilers will warn on too large integer constants
for constants that are 64-bit in length. Explicitly put a 'ULL' suffix
on those defines.
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
